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// RUN: %clangxx_tsan -O1 %s %link_libcxx_tsan -o %t && %deflake %env_tsan_opts=atexit_sleep_ms=50 %run %t 2>&1 | FileCheck --check-prefix=CHECK-REPORT %s
#include <atomic>
#include <cassert>
#include <stdio.h>
#include <thread>
#define NUM_ORDS 16
#define NUM_THREADS NUM_ORDS * 2
struct node {
int val;
};
std::atomic<node *> _nodes[NUM_THREADS] = {};
void f1(int i) {
auto n = new node();
n->val = 42;
_nodes[i].store(n, std::memory_order_release);
}
template <int version>
void f2(int i, std::memory_order mo, std::memory_order fmo) {
node *expected = nullptr;
while (expected == nullptr) {
_nodes[i].compare_exchange_weak(expected, nullptr, mo, fmo);
};
++expected->val;
assert(expected->val == 43);
}
struct MemOrdSuccFail {
std::memory_order mo;
std::memory_order fmo;
};
MemOrdSuccFail OrdList[NUM_ORDS] = {
{std::memory_order_release, std::memory_order_relaxed},
{std::memory_order_release, std::memory_order_acquire},
{std::memory_order_release, std::memory_order_consume},
{std::memory_order_release, std::memory_order_seq_cst},
{std::memory_order_acq_rel, std::memory_order_relaxed},
{std::memory_order_acq_rel, std::memory_order_acquire},
{std::memory_order_acq_rel, std::memory_order_consume},
{std::memory_order_acq_rel, std::memory_order_seq_cst},
{std::memory_order_seq_cst, std::memory_order_relaxed},
{std::memory_order_seq_cst, std::memory_order_acquire},
{std::memory_order_seq_cst, std::memory_order_consume},
{std::memory_order_seq_cst, std::memory_order_seq_cst},
{std::memory_order_relaxed, std::memory_order_relaxed},
{std::memory_order_relaxed, std::memory_order_acquire},
{std::memory_order_relaxed, std::memory_order_consume},
{std::memory_order_relaxed, std::memory_order_seq_cst},
};
int main() {
std::thread threads[NUM_THREADS];
int ords = 0;
// Instantiate a new f2 for each MO so we can dedup reports and actually
// make sure relaxed FMO triggers a warning for every different MO.
for (unsigned t = 0; t < 8; t += 2) {
threads[t] = std::thread(f1, t);
threads[t + 1] = std::thread(f2<0>, t, OrdList[ords].mo, OrdList[ords].fmo);
threads[t].join();
threads[t + 1].join();
ords++;
}
for (unsigned t = 8; t < 16; t += 2) {
threads[t] = std::thread(f1, t);
threads[t + 1] = std::thread(f2<1>, t, OrdList[ords].mo, OrdList[ords].fmo);
threads[t].join();
threads[t + 1].join();
ords++;
}
for (unsigned t = 16; t < 24; t += 2) {
threads[t] = std::thread(f1, t);
threads[t + 1] = std::thread(f2<2>, t, OrdList[ords].mo, OrdList[ords].fmo);
threads[t].join();
threads[t + 1].join();
ords++;
}
for (unsigned t = 24; t < 32; t += 2) {
threads[t] = std::thread(f1, t);
threads[t + 1] = std::thread(f2<3>, t, OrdList[ords].mo, OrdList[ords].fmo);
threads[t].join();
threads[t + 1].join();
ords++;
}
fprintf(stderr, "DONE\n");
return 0;
}
// CHECK-REPORT: WARNING: ThreadSanitizer: data race
// CHECK-REPORT: WARNING: ThreadSanitizer: data race
// CHECK-REPORT: WARNING: ThreadSanitizer: data race
// CHECK-REPORT: WARNING: ThreadSanitizer: data race
// CHECK-REPORT: DONE
// CHECK-REPORT: ThreadSanitizer: reported 4 warnings
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